In recent years, a mobile phone and a portable personal computer having a miniaturized camera incorporated therein are becoming widespread. The miniaturized camera is generally constituted of an imaging device, which is a semiconductor device such as a CMOS sensor, and a lens. As for the mobile phone and the portable personal computer, further size reduction is in progress, which requires further size reduction of the miniaturized camera to be used therefor. In order to satisfy such the requirement, there has been developed an imaging apparatus module formed by modularizing the lens with the CMOS sensor.
The patent document 1 (the official gazette of the Japanese Unexamined Patent Publication No. 2003-189195) shown below discloses an imaging apparatus having a lens modularized with an imaging device.
FIG. 1 is a cross-sectional view of an exemplary configuration of the imaging apparatus having the lens modularized with the imaging device. An imaging apparatus 40 includes a case body 41 on which an imaging lens 44 and an imaging device 10A are mounted, and a substrate 42 connecting with case body 41. Imaging device 10A is a semiconductor device such as a CMOS sensor, as an example.
Case body 41 is formed of a lens holder 41A and a resin molded body 41B in a separate manner. Lens 44 is disposed substantially at the center of lens holder 41A, and on the upper portion of lens 44, there is formed an aperture 41Aa for fetching an image into the lens. On the lower portion of lens 44, an iris 41Ab is formed, and an IR filter 45 is disposed below iris 41Ab.
Lens holder 41A is mounted on resin molded body 41B having an aperture 41Ba in the center. Resin molded body 41B has electronic components, such as a drive device of imaging device 10A, being incorporated therein, and further, an external connection terminal 41Bd is formed on a protrusion portion 41Bc being formed protrusively from a bottom face 41Bb.
On the bottom face 41Bb of resin molded body 41B, imaging device 10A is flip-chip mounted. A light-receiving face 10Aa of imaging device 10A faces opposite to lens 44 via aperture 41Ba of resin molded body 41B. With this, it is possible to form an image on light-receiving face 10Aa by means of lens 44.
Using external connection terminal 41Bd formed on bottom face 41Bb of resin molded body 41B of case body 41, case body 41 connects with substrate 42. Substrate 42, which is a flexible substrate having flexibility, is constituted of a polyimide film 42A as a base, and wiring 42B of a copper plate or a copper foil being formed on polyimide film 42A. It may also be possible to dispose wiring 42B on both sides of polyimide film 42A.
FIG. 2 is a cross-sectional view illustrating a portion of the imaging apparatus shown in FIG. 1. In FIG. 2, external connection terminal 41Bd on bottom face 41Bb of resin molded body 41B bonds to substrate 42 using solder 82, etc. Further, between substrate 42 and resin molded body 41B, an underfill material 80 is injected and filled. As underfill material 80, epoxy resin having strong adhesion force is preferable.
By filling underfill material 80 between resin molded body 41B and substrate 42, the bonding between resin molded body 41B and substrate 42 can be reinforced. In case that a flexible substrate is used as substrate 42, it becomes possible to prevent a solder bonding portion from being peeled off or the occurrence of incorrect bonding caused by degradation, even when the flexible substrate is bent repetitively.
FIG. 3 is a diagram schematically illustrating a configuration procedure of the configuration shown in FIG. 2. First, in FIG. 3(a), external connection terminal 41Bd on resin molded body 41B having imaging device 10A mounted thereon is bonded with solder to the wiring pattern of substrate 42 constituted of flexible substrate. Then, as shown in FIG. 3(b), the epoxy underfill material is injected into the bonding portion between resin molded body 41B and substrate 42, and hardened. Further, thereafter, as shown in FIG. 3(c), lens holder 41A including IR filter 45 and lens 44 are mounted on resin molded body 41B.
However, the configuration procedure shown in the above FIG. 3 has the problem shown below. Namely, when injecting and filling the underfill material between resin molded body 41B and substrate 42, it is necessary to harden the underfill material on the order of 100-200° C. using a constant temperature chamber, which complicates the manufacturing process.
Also, in the filling process for injecting and hardening the underfill material, an overall semiconductor apparatus on the way of manufacturing is exposed in a relatively high temperature atmosphere. Therefore, in order to avoid a bad influence such as lens deformation and blur caused by the high temperature, lens holder 41A having IR filter 45 and lens 44 cannot be mounted on resin molded body 41B before the completion of the underfill material filling process. Accordingly, light-receiving face 10Aa of imaging device 10A is exposed outside from when solid imaging device 10A is mounted on resin molded body 41B until the underfill material filling process is completed, which causes a risk of foreign substances such as dust and dirt being attached on light-receiving face 10Aa. Such the foreign substances being attached to light-receiving face 10Aa may affect the image.
Additionally, in the patent document 2 (the official gazette of the Japanese Unexamined Patent Publication No. Sho-57-162398) shown below, there has been disclosed a technique for configuring an electronic apparatus by disposing electronic components in a space formed by bending a reinforcement plate having a copper foil face, enabling achievement of the electromagnetic wave shield effect without a special metal case for shielding an electromagnetic wave.
Patent document 1: The official gazette of the Japanese Unexamined Patent Publication No. 2003-189195.
Patent document 2: The official gazette of the Japanese Unexamined Patent Publication No. Sho-57-162398.